Automatic switch.



F. A. LUNDQUIST.

AUTOMATIC SWITCH- APPLICATION FILED FEB. 12. i917.

1,251,985. Patented Jan. 1, 1918.

Q5 52 mg 52 Wu/KJ PATENT FRANK A. LUNDQUIST, OF CHICAGO, ILLINOIS,ASSIGNOLR, TO WESTERN ELECTRIC COMPANY, INCORPORATED, NEW YORK, N. Y., ACORPORATION OF'NEW YORK.

AUTOMATIC SWITCH.

Specification of Letters Patent.

Patented Jan. 1, 1918.

Application filed February 12, 1917. Serial No. 148,228.

To all whom it may concern Be it known that I, FRANK A. LUNDQUIST, acitizen of the United States, residing at Chica o, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Automatic Switches, of which the following is a full, clear, concise,and exact description.

This invention relates to automatic switches for use in either automaticor semiautomatic telephone exchange systems, and particularly to gravityoperated switches of the panel type; In this type of switch, sets ofcontacts are assembled in large flat-faced banks or panels over whichbrushes are allowed to drop in a straight line to engage adesired'set ofcontacts. These contacts are multiplied horizontally across the panel tobe accessible to a plurality of switches.

The object of this invention is to provide a switch of compactconstruction for rapidly connectinga subscribers line to an idle trunk.

In the preferred embodiment of this invention the contacts of each lineare carried on a movable line bar.

A feature of this invention is the longitudinal displacing of a line barin a gravity operated switch to position the contacts of the displacedline bar for arresting the movement of a gravity operated set ofbrushes.

Another feature is the longitudinal displacing of the brushes to engagecontacts on the displaced line bar.

" Other features of the invention will be apparent from the followingdescription and the appended claims.

Referring to the drawing, a perspective view of a switch employing thisinvention is shown with suitable circuit arrangements yoke-shaped member3 is slidably mounted on this rod 2 and has the teeth 4 with which aholding pawl 5, pivotally mounted on the frame 1 engages to hold theyoke 3 in its normal position.

A.pin 6 on the yoke 3 normally engages one end of a bell-crank lever 7.This lever 7 has at its other'end a fiat spring 8 which normally engagesan arm of a stepping pawl 9. This pawl 9 is pivotally mounted on the arm10 of the armature of magnet 11, so that when magnet 11 is energized thepawl 9 engages the-holding pawl 5110 release the yoke 3 instead ofengaging the teeth 1 to move the yoke 3 upward. A vertical rod 12 isslidably mounted in the frame 1 and is normally held against the lowerarm of the yoke 3 by a spring 13, one end of which is fastened to therod 12, and the other end is fastened to the upper arm of the yoke 3.Teeth 14 are cut in the rod 12 and a holding pawl 15 is arranged toengage these'teeth. A lug 16 is fastened to the rod 12 and controls abell-crank lever 17 for a purpose hereinafter described.

A block of insulation 18 is rigidly secured to the rod 12 in anysuitable manner. A pair of brushes 19 and 20, fastened together with astrip of insulation between them, are attached to the block 18 in such amanner that they have a longitudinal movement and also a lateralmovement. A pin 22 secured to the block 18 serves as a stop againstwhich the brushes are normally held by a spring 23, one endof which isfastened to the pin 22 and the other end is fastened to a pin 24 securedto the brushes. A slot 21 is provided in the brushes to allow them to bemoved longitudinally. A spring 25 engages the side of the brush 20 toreturn the brushes to their normal position after they have been movedside-wise in a manner hereinafter described. A lug 26 on the brush 20 isso arranged that when the brushes are moved longitudinally by armature28 of magnet 29 the lug engages a projection 27 of the block 18 to holdthe brushes in their operated position.

The brushes 19 and 20 are arranged to engage contacts of a group of linebars generally designated 30. Each line bar consists of two thin metalstrips 91 and 92 with a thin insulation strip between them held togetherin any suitable manner. Each metal strip has a plurality of contactsthereon and each contact of the strip 91 has a hole therein with-which aprojection 33 of the brush 20 engages for a purpose hereinafterdescribed. Each line bar is pivotally mounted in the frame and alsoarranged to be moved longitudinally.

', armature 10, which moves the pawl 9 upward battery, winding of relay36, conductor 37,

contact springs 38 and 39, conductors i and 42, subscribers substationapparatus, conductor 43, resistance a l, to ground. Relay 36 becomesenergized and closes at its armature and front contact a circuit formagnet 34, from ground, battery, front contact and armature of relay 36,winding 01 magnet 3%,

to ground. Magnet 34, by attracting its armature 35, longitudinall movesthe line bar 30 associated with the calling snbscribers line so thatcontacts thereotare in the path of the brushes of the selected switch.The armature 35 also moves spring to close a circuit for magnet 11 fromground, battery, contact springs a6, 15 and L7, starter wire 48, contactsprings 49 and 50, conductor 51, left-hand armature and back contact ofrelay 52, conductor 53, winding o1 magnet 11, to ground. Simultaneouslya circuit is closed for magnet 29 from ground, battery, contactspringsxl o and l5, starter wire 5%, contact springs 55 and 56,conductor 57, winding of magnet 29, to ground. Magnet 29, by attractingits armature 28, longitudinally moves the brushes 19 and 20 to positionthem so that they will engage contacts or the displaced line bar. Thebrushes are held in their operative position by the lug 26 engaging thecatch 27 Magnet 11, upon becoming energized over the circuit previouslydescribed, attracts its under the control of spring 8, to engage andwithdraw holding pawl 5 from the teeth The brushes 19 and 20 will thenbe free to drop by gravity into engagement with the contacts 31 and 32of the displaced line bar 30. The catch 58 of the armature engages aprojection 59 of the spring 4E9 to maintain the contact between springsl9 and 50 closed as long as magnet 11 is energized.

As soon as the yoke 3, which slides down with brushes, leaves itsnormalposition the bell-crank lever is moved against the stop 70 by spring 71.This movement of the bell crank lever closes contact springs 66 and 67 iand also moves spring 8 into a position to allow pawl 9 to engage teeth4: so that when the magnet 11 is subsequently operated the yoke 3 willbe stepped upward. Since the magnet 11 is at this time energized overthe circuit above described the pawl 9 is pre vented from engaging theteeth a because it is held in the notch in the lower portion of the pawl5 into which it was moved by the first energization of the magnet 11.

hen the brushes 19 and 20 are stopped by engaging contacts 31 and 32 01the displaced line bar, the weight of the rod 12 and the apparatusattached thereto is carried by the brushes and the line bar and thisweight is suliicient to bend the brushes upward so that the lug 26disengages the catch 27 and allows the brushes to be moved slightly tothe left, a distance determined by the pin 33, and the size oi theoval-shaped hole in the contact 31, and the weight of the rod 12 alsocauses the line bar to rotate so that its arm 59 slips oil the arm 60 ofthe armature 35. The spring 61 then moves the line bar back to itsnormal longitudinal position, thereby moving the contacts thereon out ofthe path or subsequently operated switches.

iihnce the pin is in the hole of the contact 31 the brushes 19 and 20will be moved sidewise by this movement of the line bar. The rotation oithe line bar also separates contact springs 38 and 39, thereby openingthe circ it of relay 36, which by becoming deerergizcd opens the circuitof magnet 3L. gnet3l by retracting its armature causes springs -15, at;and -l7 to separate from each other, thereby opening the circuits ofmagets 11 and 29. The magnet 29 by retracting s armature allows thebell-crank lever 17 o engage the stop 73. This lever 17 was reeased bythe lug 16 as soon as the rod 12 left its normal position, but wasprevented from moving by the attracted armature 28. The retraction ofthe armature 28 also moves the pawl 15 into engagement with the teethl-il to prevent the rod 12 and brushes;

thereon from moving back to their normal position. Rod 17, by movingfrom its norma] position, opens the contact between springs and 56 andcloses the contact between 56 and H, and between springs and 7 5. Theclosure ot' springs 55 and extends the starter wire 5 l to the next idleswitch.

Upon engagement of the brush 19 with contact 32 a circuit for relay 62is closed from ground, battery, winding of relay 62, conductor 63.,brush 19, contact 32, terminal strip 92, conductor 42, subscriberssubstation appantus, conductor l3, resistance ii, to ground. Relay 62becomes energized and closes a circuit for relay 52 from ground,battery, armature and from; contact of relay 62, conductor 6%, windingof relay 52, to ground. Relay 52 closes at its right-hand armature andfront contact a circuit for magnet 11 from ground, battery, right-handarmature and front con 'act, of relay 52, conductor 65, contact springs66 and 67, conductor 68, contact springs 76 and 77, conductor 78,winding of magnet 11, to ground.

Magnet 11 now attracts its armature 10 and the pawl 9 under the controlof springs 8 and 79 engages the teeth 1 to raise the yoke 3. Since thecircuit for magnet 11 is opened by the attraction of its armature themagnet will be intermittently energized and de'elnergized until the rackhas been stepped back to its normal position, t which time the pin 6engages the bell-crank lever 7 and open contact springs 66 and 6?, whichpermanently breaks the circuit for magnet 11. The rod 12 is preventedfrom moving upward at this time by pawl 15 being in engagement withteeth 14: and, therefore, spring 13 is placed under tension by thisupward movement of the -ack to return the rod 12 to its normal positionupon the release of the switch.

Relay 52 is slow to release its armatures so that it will remainenergized during the sending of impulses by the subscriber.

At the end of conversation, the subscriber A replaces his receiver onthe hook, thereby opening the circuit of relay 62, which, upon becomingdeenergized, opens at its armature th circuit of relay 52. Relay 52, byretract ing its armatures, closes a circuit for magnet 29 from ground,battery, right-hand armature and back contact of relay 52, conductor 93,contact springs 7st and 56, conductor 57, winding of magnet 29, toground. Magnet 29, by attracting its armature 28, withdraws pawl 15 fromengagement with teeth 14:, thereby allowing the rod 12, carrying thebrushes 19 and 20, to return to its normal position. Upon the rod 12reaching its normal position the lug 16 engages the bellcrank lever 17,thereby opening contact springs 56 and 74, causing the deenergization ofmagnet 29. The lug 80, in the normal position of the rod 12, closessprings 49 and to connect magnet 11 to the starter circuit so that thisswitch is now ready for another call.

hat is claimed is:

1. In an automatic switch, a plurality of line bars, contacts on saidline bars, a gravity operated set of brushes to cotiperate with saidcontacts, means for releasing said set of brushes, and means forlongitudinally displacing a line bar to position its contacts to arrestthe movement of said set of brushes.

2. In an automatic switch, a plurality of line bars, contacts on saidline bars, a gravity operated set of brushes to cooperate with saidcontacts, means for releasing said set of brushes, means forlongitudinally displacin a line bar to position its contacts 'to arrestthe movement of said set of operated sets of brushes.

In an automatic switch, a plurality of line bars in which subscriberslines terminate, one of said line bars being associated with each line,contacts on said line bars, a gravity opera ted set ot brushes arrangedwhen released to traverse and engage said contacts, means operated uponthe initiation of a call upon a line for longitudinally displacing theli bar associated therewith to position the contacts thereof in the pathof said set of brushes, and means actuated upon the operation of saidmeans "for releasing said set of brushes.

4. In an automatic switch, a plurality of contact terminals, a gravityoperated set off brushes to coiiperate with said terminals, means forreleasing said set of brushes, and means for longitudinally displacingsaid terminals to engage said set of brushes.

5. In an automatic switch, a plurality of line bars in which subscriberslines terminate, a line bar being associated with each line, contacts onsaid line bars, a gravity operated set of brushes arranged when releasedto traverse and engage said contacts, and means operated upon theinitiation of a call on one of said lines for simultaneously releasingsaid set of brushes and for longitudinally displacing said brushes toengage said contacts.

6. In an automatic switch, a plurality of line bars in which subscriberslines terminate, a line bar being associated with each line, contacts onsaid line bars, a gravity operated set oi brushes arranged when releasedto traverse and engage said contacts, and means operated upon theinitiation of a call on one of said lines for longitudinally displacingthe line bar associated with said line, for releasing said set ofbrushes, and for displacing said brushes to engage contacts on thedisplaced line bar.

7. In an automatic switch, a plurality of line bars in which subscriberslines terminate, a line bar being associated with each line, contacts onsaid line bars, a gravity operated set of brushes arranged when releasedto trai 'erse and engage said contacts, means operated upon theinitiation of a call on one of said lines for longitudinally displacingthe line bar associated with said line. for releasing said set ofbrushes and for displacing said brushes to engage contacts on thedisplaced line bar, and means responsive to the engagement of thebrushes ith the last mentioned contacts for removing said line bar fromthe path of subsequently operated brushes.

8. In an automatic switch, a plurality of line bars, contacts on saidbars, a gravity operated set of brushes to cooperate with said contacts,means for releasing said set of brushes, a magnet individual to each ofsaid. line bars and arranged to longitudinally displace said line bar toposition the contacts thereof to arrest the movement of said set ofbrushes.

9. In an automatic switch, a plurality of line bars, contacts on saidbars, a gravity perated set of brushes to cooperate with said contacts,means for releasing said set of brushes, a magnet individual to each ofsaid line bars and arranged to longitudinally displace said line bar toposition the contacts thereof to arrest the movement of 10 said set ofbrushes, and means responsive to the engagement of the brushes withcontacts of the displaced line bar for removing said line from the pathof subsequently operated brushes.

In Witness whereof, I hereunto subscribe my name this 6th day of Feb, A.D. 1917.

FRANK A. LUNDQUIST.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner oi Patents,

Washington, D. C.

